WIP Adding more graphical projection drawing tools

Stubbing out tools for drawing in axonometric projection -- Isometric,
Dimetric, Trimetric -- and in oblique projection.

Also, placed 1-, 2-, and 3-point perspective tools, along with these
new ones, into a new Magic Tool group, MAGIC_TYPE_PROJECTIONS.

See https://sourceforge.net/p/tuxpaint/feature-requests/252/
and https://sourceforge.net/p/tuxpaint/feature-requests/253/

docs/CHANGES.txt

@@ -6,7 +6,7 @@ Copyright (c) 2002-2024
 Various contributors (see below, and AUTHORS.txt)
 https://tuxpaint.org/
 
-2024.January.8 (0.9.32)
+2024.January.12 (0.9.32)
   * Improvements to Magic tools:
     ----------------------------
     * Support for complexity levels in Magic tools via the plugin API.
@@ -25,23 +25,41 @@ https://tuxpaint.org/
 
   * New Magic Tools:
     ----------------
-    * Vanishing point magic tools:
+    * WIP Tools to draw with various kinds of graphical projections
-      + 1-point Perspective ("1-Point Select" & "1-Point Draw")
+      (all placed within a new tool group):
-        Choose a vanishing point, and then draw lines that always
+      + Point-projection persepctive:
-        point towards it, or are vertical or horizontal.
+        - 1-point Perspective ("1-Point Select" & "1-Point Draw")
-      + 2-point Perspective ("2-Point Select" & "2-Point Draw")
+          Choose a vanishing point, and then draw lines that always
-        Choose two vanishing points, and then draw lines that always
+          point towards it, or are vertical or horizontal.
-        point towards them, along the horizon defined by them,
+        - 2-point Perspective ("2-Point Select" & "2-Point Draw")
-        or perpendicular to that horizon.
+          Choose two vanishing points, and then draw lines that always
-      + 3-point Perspective ("3-Point Select" & "3-Point Draw")
+          point towards them, along the horizon defined by them,
-        Choose three vanishing points, and then draw lines that always
+          or perpendicular to that horizon.
-        point towards them, or along the horizon defined by the first two.
+        - 3-point Perspective ("3-Point Select" & "3-Point Draw")
+          Choose three vanishing points, and then draw lines that always
+          point towards them, or along the horizon defined by the first two.
+      + WIP Orthographic (orthogonal) projection:
+        - WIP Isometric ("Isometric Lines")
+          Lines only go at evenly-spaced (120 degrees) angles (vertically
+          and diagonally).
+        - WIP Dimetric ("Dimetric Select" & "Dimetric Draw")
+          Choose a single angle for both diagonals directions; lines may
+          only go diagonally at those angles, or vertically.
+        - WIP Dimetric ("Trimetric Select" & "Trimetric Draw")
+          Choose an angle for two diagonals directions; lines may
+          only go diagonally at those angles, or vertically.
+        - WIP Oblique ("Oblique Select" & "Oblique Draw")
+          Choose an angle for a single diagonal direction; lines may
+          only go diagonally at that one angle, vertically, or
+          horizontally.
       + None of these tools are available when in "novice" complexity mode
         (see above).
-      + "Select" tools (to edit vanishing points) are not offered
+      + "Select" tools (to edit vanishing points or angles) are not offered
-        when in "beginner" complexity mode.
+        when in "beginner" complexity mode.  However, in "beginner" mode:
-        - Also, two "3-Point Draw" tools are provided in "beginner"
+        - Two "3-Point Draw" tools are provided, offering both 'upwards'
-          mode, to offer both 'looking up' and 'looking down' perspectives.
+          and 'downwards' perspectives.
+        - WIP Two "Oblqiue" tools are provided, offering recedings axes
+          to both the right and the left.
       + Code: Bill Kendrick <bill@newbreedsoftware.com>
       + Sounds:
         - Select: "Gummibandloop_121.wav"

magic/src/n_pt_persp.c

@@ -1,6 +1,7 @@
 /* n_pt_persp.c
 
-   1-, 2-, and 3-point perspective line-drawing tools.
+   1-, 2-, and 3-point perspective, axonometric (isometric, dimetric,
+   and trimetric), and oblique line-drawing tools,
 
    Different complexity (expertise) levels offer different
    tools.  In Advanced mode, there are "Draw" and "Select"
@@ -12,7 +13,7 @@
 
    by Bill Kendrick <bill@newbreedsoftware.com>
 
-   December 12, 2023 - December 30, 2023
+   December 12, 2023 - January 12, 2024
 */
 
 
@@ -29,14 +30,37 @@
 /* All _possible_ tools */
 enum
 {
-  TOOL_1PT_SELECT, /* advanced & beginner */
+  /* 1-point perspective */
-  TOOL_1PT_DRAW, /* advanced only */
+  TOOL_1PT_SELECT, /* advanced only */
-  TOOL_2PT_SELECT, /* advanced & beginner */
+  TOOL_1PT_DRAW, /* advanced & beginner */
-  TOOL_2PT_DRAW, /* advanced only */
+
-  TOOL_3PT_SELECT, /* advanced & beginner */
+  /* 2-point perspective */
-  TOOL_3PT_DRAW, /* advanced only */
+  TOOL_2PT_SELECT, /* advanced only */
-  TOOL_3PT_SELECT_ALT, /* beginner only (not directly accessible; used for drawing guideS) */
+  TOOL_2PT_DRAW, /* advanced & beginner */
+
+  /* 3-point perspective */
+  TOOL_3PT_SELECT, /* advanced only */
+  TOOL_3PT_DRAW, /* advanced & beginner */
+  TOOL_3PT_SELECT_ALT, /* beginner only (not directly accessible; used for drawing guides) */
   TOOL_3PT_DRAW_ALT, /* beginner only */
+
+  /* Isometric */
+  TOOL_ISO_DRAW, /* advanced & beginner (N.B. isometric defined by exact angles; no "SELECT" tool) */
+
+  /* Dimetric */
+  TOOL_DIM_SELECT, /* advanced only */
+  TOOL_DIM_DRAW, /* advanced & beginner */
+
+  /* Trimetric */
+  TOOL_TRI_SELECT, /* advanced only */
+  TOOL_TRI_DRAW, /* advanced & beginner */
+
+  /* Oblique */
+  TOOL_OBLQ_SELECT, /* advanced only */
+  TOOL_OBLQ_DRAW, /* advanced & beginner */
+  TOOL_OBLQ_SELECT_ALT, /* beginner only (not directly accessible; used for drawing guides) */
+  TOOL_OBLQ_DRAW_ALT, /* beginner only */
+
   NUM_TOOLS
 };
 
@@ -44,14 +68,36 @@ enum
 
 #ifdef DEBUG
 char * tool_debug_names[NUM_TOOLS] = {
+  /* 1-point perspective */
   "1pt select",
   "1pt draw",
+
+  /* 2-point perspective */
   "2pt select",
   "2pt draw",
+
+  /* 3-point perspective */
   "3pt select",
   "3pt draw",
   "3pt select alt",
   "3pt draw alt",
+
+  /* Isometric */
+  "iso draw",
+
+  /* Dimetric */
+  "dim select",
+  "dim draw",
+
+  /* Trimetric */
+  "tri select",
+  "tri draw",
+
+  /* Oblique */
+  "oblq select alt",
+  "oblq draw alt",
+  "oblq select",
+  "oblq draw",
 };
 #endif
 
@@ -59,8 +105,8 @@ Uint8 complexity;
 
 int num_tools[NUM_MAGIC_COMPLEXITY_LEVELS] = {
   0, /* Novice */
-  4, /* Beginner */
+  9, /* Beginner */
-  6, /* Advanced */
+  13, /* Advanced */
 };
 
 int * which_to_tool;
@@ -68,12 +114,8 @@ int * which_to_tool;
 int which_to_tool_per_complexity[NUM_MAGIC_COMPLEXITY_LEVELS][NUM_TOOLS] = {
   /* Novice */
   {
-    -1,
+    -1, -1, -1, -1, -1, -1, -1, -1,
-    -1,
+    -1, -1, -1, -1, -1, -1, -1, -1,
-    -1,
-    -1,
-    -1,
-    -1,
     -1,
   },
   /* Beginner */
@@ -82,9 +124,12 @@ int which_to_tool_per_complexity[NUM_MAGIC_COMPLEXITY_LEVELS][NUM_TOOLS] = {
     TOOL_2PT_DRAW,
     TOOL_3PT_DRAW,
     TOOL_3PT_DRAW_ALT,
-    -1,
+    TOOL_ISO_DRAW,
-    -1,
+    TOOL_DIM_DRAW,
-    -1,
+    TOOL_TRI_DRAW,
+    TOOL_OBLQ_DRAW,
+    TOOL_OBLQ_DRAW_ALT,
+    -1, -1, -1, -1, -1, -1, -1, -1,
   },
   /* Advanced */
   {
@@ -94,43 +139,116 @@ int which_to_tool_per_complexity[NUM_MAGIC_COMPLEXITY_LEVELS][NUM_TOOLS] = {
     TOOL_2PT_DRAW,
     TOOL_3PT_SELECT,
     TOOL_3PT_DRAW,
-    -1,
+    TOOL_ISO_DRAW,
+    TOOL_DIM_SELECT,
+    TOOL_DIM_DRAW,
+    TOOL_TRI_SELECT,
+    TOOL_TRI_DRAW,
+    TOOL_OBLQ_SELECT,
+    TOOL_OBLQ_DRAW,
+    -1, -1, -1, -1,
   },
 };
 
 const char *icon_filenames[NUM_TOOLS] = {
+  /* 1-point perspective */
   "1pt_persp_select.png",
   "1pt_persp_draw.png",
+
+  /* 2-point perspective */
   "2pt_persp_select.png",
   "2pt_persp_draw.png",
+
+  /* 3-point perspective */
   "3pt_persp_select.png",
   "3pt_persp_draw.png",
   "",
   "3pt_persp_draw_alt.png",
+
+  /* Isometric */
+  "Snow_flake4.png", // FIXME
+
+  /* Dimetric */
+  "Snow_flake4.png", // FIXME
+  "Snow_flake4.png", // FIXME
+
+  /* Trimetric */
+  "Snow_flake4.png", // FIXME
+  "Snow_flake4.png", // FIXME
+
+  /* Oblique */
+  "Snow_flake4.png", // FIXME
+  "Snow_flake4.png", // FIXME
+  "",
+  "Snow_flake4.png", // FIXME
 };
 
 
 const char *tool_names[NUM_TOOLS] = {
+  /* 1-point perspective */
   gettext_noop("1-Point Select"),
   gettext_noop("1-Point Draw"),
+
+  /* 2-point perspective */
   gettext_noop("2-Point Select"),
   gettext_noop("2-Point Draw"),
+
+  /* 3-point perspective */
   gettext_noop("3-Point Select"),
   gettext_noop("3-Point Draw"),
   "",
   gettext_noop("3-Point Draw Down"),
+
+  /* Isometric */
+  gettext_noop("Isometric Lines"),
+
+  /* Dimetric */
+  gettext_noop("Dimetric Select"),
+  gettext_noop("Dimetric Draw"),
+
+  /* Trimetric */
+  gettext_noop("Trimetric Select"),
+  gettext_noop("Trimetric Draw"),
+
+  /* Oblique */
+  gettext_noop("Oblique Select"),
+  gettext_noop("Oblique Draw"),
+  "",
+  gettext_noop("Oblique Draw Left"),
 };
 
 
 const char *tool_descriptions[NUM_TOOLS] = {
+  /* 1-point perspective */
   gettext_noop("Click in your drawing to pick a vanishing point for the 1-point perspective painting tool."),
   gettext_noop("Click and drag to draw lines with your 1-point perspective vanishing point."),
+
+  /* 2-point perspective */
   gettext_noop("Click two places in your drawing to pick vanishing points for the 2-point perspective painting tool."),
   gettext_noop("Click and drag to draw lines with your 2-point perspective vanishing points."),
+
+  /* 3-point perspective */
   gettext_noop("Click three places in your drawing to pick vanishing points for the 3-point perspective painting tool."),
   gettext_noop("Click and drag to draw lines with your 3-point perspective vanishing points."),
   "",
   gettext_noop("Click and drag to draw lines with your 3-point perspective vanishing points (downward perspective)."),
+
+  /* Isometric */
+  gettext_noop("Click and drag to draw lines with an isometric projection."),
+
+  /* Dimetric */
+  gettext_noop("Click in your drawing to adjust the angle used by the dimetric projection painting tool."),
+  gettext_noop("Click and drag to draw lines with dimetric projection."),
+
+  /* Trimetric */
+  gettext_noop("Click in your drawing to adjust the angles used by the trimetric projection painting tool."),
+  gettext_noop("Click and drag to draw lines with trimetric projection."),
+
+  /* Oblique */
+  gettext_noop("Click in your drawing to adjust the angle used by the oblique projection painting tool."),
+  gettext_noop("Click and drag to draw lines with oblique projection."),
+  "",
+  gettext_noop("Click and drag to draw lines with oblique projection (right-facing)."),
 };
 
 
@@ -344,7 +462,7 @@ char *n_pt_persp_get_name(magic_api * api ATTRIBUTE_UNUSED, int which)
 
 int n_pt_persp_get_group(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED)
 {
-  return (MAGIC_TYPE_PAINTING);
+  return (MAGIC_TYPE_PROJECTIONS);
 }
 
 

src/tp_magic_api.h.in

@@ -183,6 +183,7 @@ enum {
   MAGIC_TYPE_PAINTING,
   MAGIC_TYPE_PATTERN_PAINTING,
   MAGIC_TYPE_PICTURE_DECORATIONS,
+  MAGIC_TYPE_PROJECTIONS,
   MAGIC_TYPE_ARTISTIC
 };